It's not often I come across something in Python that surprises me. Especially in something as mundane as string operations, but I guess Python still has a trick or two up its sleeve.
Have a look at this string:
How many possible sub-strings are in s? To put it another away, how many values of x are there where the expression x in s is true?
Turns out it is 2.
2?
Yes, 2.
The empty string is in the string "A". In fact, it's in all the strings.
Turns out the empty string has been hiding every where in my code.
Not a complaint, I'm sure the rationale is completely sound. And it turned out to be quite useful. I had a couple of lines of code that looked something like this: continue reading…